Magneto generator



Feb. 20, 1940. w. .LSPENGLER 2,191,087

MAGNETO GENERATOR Original-Filed Feb. 25, 19:53

INVENTOR BY (Jamie/id Spengler 1%. A RNEY.

Patented Feb. 20, 1940 UNITED STATES PATENT OFFICE MAGNETO GENERATOR Walter J. Spengler, Sidney, N. Y., assignor to Bendix Aviation Corporation, South Bend, Ind., a corporation of Delaware 1935, Serial No. 24,476

3 Claims.

The present invention relates to magneto generators and more particularly to circuit breaker mechanism for ignition magnetos.

The present application is a division of the co- 5 pending application, Serial Number 658,614, filed February 25, 1933, now Patent 2,012,290, August 27, 1935.

It is an object of the present invention to provide novel and improved circuit breaker mechal nism for ignition magnetos particularly adapted for high speed operation.

It is another object to provide such a device in which wear of the breaker parts is reduced to a minimum.

5 It is a further object to provide such a device embodying means for the efficient and continu ous lubrication of the moving parts.

It is another object to provide such a device in which the timing and adjustment of the 0 breaker mechanism is convenient and readily observable.

Further objects and advantages will be apparent to those skilled in this art from the following description taken in connection with the accompanying drawing in which:

Fig. 1 is a View of the breaker end of a magneto incorporating a preferred embodiment of the present invention, the cover of the breaker being removed;

30 Fig. 2 is a vertical section of a portion of said magneto taken substantially on the line 2--2 of Fig. l; and

Fig. 3 is a rear view of the carrier element for the breaker mechanism showing particularly the r, adjustment limiting means.

Referring first to Fig. 1 of the drawing, there is illustrated a portion of a magneto having a frame or casing indicated generally by numeral I having a rotor shaft I! journalled therein car- A o rying a cam 46 rigidly mounted thereon by suitable means such as a key 41 and stud 48, said cam being arranged to extend outwardly from the frame of the magneto I a considerable distance. A breaker assembly is mounted for rotary ad- 43 justment in the end of the casing I in position to be actuated by the cam 46. This breaker, assembly comprises a cup-shaped carrier 49 arranged to seat in a circular flange 5| on the end of the casing i and to be retained therein by 50 means of an elastic hook member 52 (Fig. 1)

swivelled inside the carrier member 49 and adapted to engage a pair of anchorages in the form of pins 53 fixed in the end of casing l and projecting through slots 54 in the bottom of the 5 carrier 49.

A fixed contact 55 is adjustably mounted in the carrier 49 as by means of sliding. bracket member 56 flied to the carrier 49 by means of studs 51 insulated from said carrier but connected to a conducting plate 58 (Fig. 2) at the back 5 of said carrier.

A movable contact 59 (Fig. 1) is mounted on a spring contact arm 6| anchored at 62 to a bracket 63 fixed to the carrier 49by means of studs 64. The arm 6| is normally tensioned so as to hold the movable contact 59 against the fixed-contact 55 with a suitable pressure and is preferably stiffened at and adjacent to its free end as by means of flanges 65 formed thereon in order to prevent harmonic vibrations of the arm. A cam follower 66 is mounted on a spring arm 6'! also anchored at 62 to the bracket 63, in position to cooperate with the cam 46, and is provided with an extension 68 arranged to engage near its free end the breaker arm 6| to move contact 59 away from contact 55 when the cam follower 66 is on a lobe of said cam. The spring arm 61 is tensioned to maintain the cam follower 66 in engagement with the cam 46 at all times,'and means in the form of a hook-shaped element 69 is provided for limit- 05 ing the inward motion of the follower. The primary purpose of thus limiting the inward motion of the cam follower 66 is to facilitate the assembly of the breaker unit on the frame I, since it is merely necessary to slightly bevel the end of the cam 46 as indicated at 'H' to insure that the cam follower does not interfere with the assembly operation by abutting on the end of the cam.

It will be particularly noted that the common anchorage of the breaker arm 6! and the cam follower 66 at 62 prevents any sliding action taking place between the portion 68 of the cam follower 66 and said spring arm during the actuation of the spring arm by the cam follower. This prevents wear at this point and correspondingly increases the life of the parts.

Means are provided for insuring efficient and continuous lubrication of the bearing surfaces of the cam 46 and cam follower 66 in the form of an oil wick l2 fixed to the back of the cam follower 66 as by means of the rivets 13 which hold the cam follower on the spring arm 61, suitable spacing thimbles 14 around the rivets where they traverse the wick 72 being provided to prevent undue compression of the wick at these points. The cam follower 66 is provided with an opening 15 therethrough adjacent its bearing surface, and the wick 12 is preferably compressed into the space at the rear of this opening so as to furnish a supply of lubricant through said opening. The wick may if desired be extended as indicated at 15 to the bottom portion of the carrier 49 in order to pick up lubricant therefrom.

The fixed contact 55 is readily adjustable longitudinally by loosening the studs 51 and placing an instrument such as a screw driver with its point in one or the other of the depressions II or 18 in the carrier 49 adjacent the ends of the bracket 56, and using such instrument as a lever to slide the bracket. Adjustment of the contact 55 axially of the rotor in order to line it up with the contact 59 may be effected by the use of shims beneath the bracket 63. The contact 59 is adjustable laterally with respect to the contact 55 to secure accurate alinement thereof by forming the opening for one of the studs 54 in the bracket 69 larger than necessary so that the bracket may pivot around the other stud 54 to secure such adjustment. 1

It will be noted that the cam and contacts and 59 all extend axially beyond the carrier 49 whereby observation and adjustment of the contacts when the magneto is mounted in a confined position are greatly facilitated.

A suitable cover" I9 (Fig. 2) is provided for sealing the breaker mechanism, and is preferably attached to the carrier 49 by readily detachable means such as the knurled studs 8| engaging in threaded openings in said carrier.

It-will be notedthat since the cam follower 5 5 always remains in engagement with the cam 45, the time of breaking of contacts 55 and 59 may be adjusted by sliding the bracket 55 back and forth irrespective of the maximum opening of said contacts or of any pitting thereof. In order to adjust the timing in accordance with the running conditions of the engine, an arm 91 (Fi 1) is adjustably clamped as indicated at 99 to the cal-- rier l9 andis adapted to be operated by a suitable linkage to rotate the carrier in order to advance or retard the time of the breaking of the contacts. This forms a secondary timing adjustment.

In the operation of this device, rotation of the rotor shaft' ll causes, rotation of the cam 4'5 which moves the follower 55 to engage the movable contact arm 5| and cause the latter to operate contact 55 to open and close the prlmarycircult of the magneto. Adjustment of the timing of the spark during the operation of, the magneto may be accomplished in the usual manner.

tion has been illustrated which comprises certain.

detailed structural features, it will be understood that the structural details are not necessarilyexclusive and that changes may be made in the dimensions and arrangements of the parts without departing from the spirit of the invention as defined in the claims appended hereto.

What is claimed is:

1. In apparatus of the class described, a cam 5 and a breaker assembly to be operated thereby including a cam follower, means for maintaining said follower continuously in engagementwith said cam, a fixed contact, a movable contact, a

spring arm carrying said movable contact and i0 maintaining it normally in engagement with the fixed contact, and an abutment on said cam follower movable by said cam into engagement with said spring arm to positively disengage the movable contact from the fixed contact, said cam 15 follower and spring arm being so mounted that their lateral movement in unison takes place 'without substantial relative translation.

'2. In apparatus of the class described, a cam,

and a breaker assembly including a fixed contact, I)

cam follower means including resilient support- 25 ing means ,fixed at one end adjacent the fixed end of'said breaker arm, an element carried by said supporting means and movable by said cam to engage and move said breaker arm to disengage said contacts, said element having an orifice i therethrbugh, said cam follower means and breaker arm being thus so mounted and arranged that substantially no relative movement occurs between the engaging portions thereof during the contact opening movement of the' same, an 35 oil soaked wick secured between said supporting means and element whereby oil is supplied from the wick to the surface -of the cam and the hearing surface of the element through said orifice.

3. I'n apparatus of the class described, a cam 4 and a breaker assembly including a breaker am having a resilient part adjacent at least one end thereof, means for fixedly mounting said end, a contact mounted on said arm adjacent the other end thereof for movement therewith, a fixed con- 4'5 tact, said first-named contact being normally held in engagement with said fixed contact by said resilient part, cam follower means having a resilient portion fixed at substantially the same point as said breaker arm and a portion conso tinuouslyheld in engagement with said cam by said resilient portion, said cam engaging portion being movable by said cam to engage and actuate said breaker arm to disengage said contacts, said I cam follower means and breaker arm being thus 5 i so mounted and arranged that substantially no relative movement occurs between the engaging portions thereof during the contact opening movement of the same.

WALTER. J. SPENGLER. 

